#include<stdio.h>
union arr  //共用体 union
{
    int c;
    char a[10];
    float b;
};

enum arr1  //枚举，枚举元素会有默认的值，是整数,第一个元素默认的值为0，递增
{
    up,
    down,
    left,
    right
};

struct Student  //结构体 struct
{
    int ID;
    char name[10];
    float score;
};

int main()
{
    struct Student arr[3]={
        {1,"张三",60.5},
        {2,"李四",70.5},
        {3,"王五",80.5}
        };
for (int i = 0; i < 3; i++)
{
    printf("%d\t%s\t%g\n",arr[i].ID,arr[i].name,arr[i].score);
}
}